BACKGROUND: The infusion of citrate during apheresis may affect the levels of ionized magnesium in the blood. Hypomagnesemia and concomitant hypocalcemia could influence the parathormone response and could be responsible for some of the symptoms observed during apheresis. STUDY DESIGN AND METHODS: The study reports measurement of ionized magnesium by the new ion-selective electrode technique in response to citrate infusion in 15 donors undergoing continuous flow high-yield plateletpheresis. The monitoring included measurement of ionized calcium and parathormone every 30 minutes during the 120-minute apheresis (plus the next 30 minutes to assess recovery). RESULTS: Ionized magnesium fell by 30 +/- 4 percent (mean +/- SD, p<0.01), which contrasts with minor changes in total concentrations. Comparison of variations in the levels of ionized and total magnesium found major formation of complexes during citrate infusion. Ionized calcium fell by 15 +/- 3 percent (p<0.01), while parathormone peaked at 356 +/- 114 percent (p<0.01) of initial value after 30 minutes. Ionized cations and parathormone recovered by more than 50 percent within 30 minutes of the end of apheresis. CONCLUSION: An acute and steep drop in ionized magnesium occurs during citrate administration. The measurement of ionized magnesium should be included in future prospective studies of donor safety and parathormone regulation during apheresis.
BACKGROUND: The infusion of citrate during apheresis may affect the levels of ionizedmagnesium in the blood. Hypomagnesemia and concomitant hypocalcemia could influence the parathormone response and could be responsible for some of the symptoms observed during apheresis. STUDY DESIGN AND METHODS: The study reports measurement of ionizedmagnesium by the new ion-selective electrode technique in response to citrate infusion in 15 donors undergoing continuous flow high-yield plateletpheresis. The monitoring included measurement of ionizedcalcium and parathormone every 30 minutes during the 120-minute apheresis (plus the next 30 minutes to assess recovery). RESULTS:Ionizedmagnesium fell by 30 +/- 4 percent (mean +/- SD, p<0.01), which contrasts with minor changes in total concentrations. Comparison of variations in the levels of ionized and total magnesium found major formation of complexes during citrate infusion. Ionizedcalcium fell by 15 +/- 3 percent (p<0.01), while parathormone peaked at 356 +/- 114 percent (p<0.01) of initial value after 30 minutes. Ionized cations and parathormone recovered by more than 50 percent within 30 minutes of the end of apheresis. CONCLUSION: An acute and steep drop in ionizedmagnesium occurs during citrate administration. The measurement of ionizedmagnesium should be included in future prospective studies of donor safety and parathormone regulation during apheresis.
Authors: Maria Helena Barbosa; Karla Fabiana Nunes da Silva; Dieska Quintiliano Coelho; Jordânia Lumênia Tavares; Luciana Falcão da Cruz; Márcia Helena Kanda Journal: Rev Bras Hematol Hemoter Date: 2014-04-03